1. Field of the Invention
The present invention relates to the technical field of TFT-LCD (Thin Film Transistor-Liquid Crystal Display) manufacturing process, and in particular to an alignment device of cutting machine.
2. The Related Arts
A liquid crystal display is commonly abbreviated as LCD, and the operation principle is placing liquid crystal molecules between two parallel pieces of glass. A plurality of tiny vertical and horizontal conductive wires is arranged between the pieces of glass and change of direction of the liquid crystal molecules is controlled through application of electricity so as to refract light out to form an image. The liquid crystal display is now widely used due to various advantages of being compact in size, saving of power, and being free of radiations. In the state-of-the-art manufacturing techniques of liquid crystal display devices, it is common to form a plurality of liquid crystal display units on a large-sized glass substrate. In such a manufacturing process, the glass substrate must be cut into a number of liquid crystal display units for the subsequent processing to be carried out. With the development of the manufacturing technique of liquid crystal display device, the liquid crystal panel is going toward higher generation and the size and weight of the glass substrate is getting greater and greater. In the manufacturing process of liquid crystal display device, the glass substrate is heaviest in the time period that is behind vacuum panel alignment and before cutting. Consequently, for pre-alignment done before cutting, it is often that an excessive frictional force is induced by the excessively heavy weight of the substrate so as to result in an issue of alignment abnormality.
To overcome such a problem, the known cutting machines, such as 8.5-generation cutting machine (Non-Cross Type) of Mitsuboshi Diamond Industrial Co., Ltd., Japan, carry out pre-alignment, initial cutting, and secondary cutting by providing a float pad on a work table for the performance of alignment. As shown in FIG. 1, the cutting machine comprises a machine body (not shown), a stand 100, and a float pad 200 mounted on the stand 100. The float pad 200 is made of a porous carbon fiber material. The way of alignment of the float pad 200 is that a glass substrate is positioned on the float pad 200 and dry air is blown out of small pores of the float pad 200. This is equivalent to reducing, to some extents, most of the gravitational force of the glass substrate so that excellent alignment can be realized. However, the porous carbon fiber material is excessively expensive and this increases the manufacturing cost to quite an extent, making it detrimental to popularization.